Seat Ibiza rough running and check engine light

Those symptoms sound really familiar. My Ibiza had the same thing. Sluggish engine, worse fuel consumption, and the check engine light was always on. Have you looked for vacuum leaks around the intake manifold? That's where my problem was. The manifold pressure sensor, or MAP sensor, needs good pressure readings. A vacuum leak messes it up. It's easy to get to on our cars, at least on mine. Tell me what you find

Intake manifold Where should I look, or are there parts that leak more often

Yeah. On my engine, the rubber hoses to the intake manifold were the issue. They get brittle and crack, causing leaks. A smoke test will find it, but you might see it if you look closely. With your symptoms, especially the power loss and slow response, a bad MAP sensor from a vacuum leak is likely. If you don't want to do it yourself, take it to a good shop to get the sensor changed

Ibiza fixed It was the manifold pressure sensor, like you thought. The shop found a big vacuum leak. New sensor fitted for 235€. It's running great now. Thanks for the guidance